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					                Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz




  Compatibility Between VDSL & PLT Systems And Radio
   Services that Operate in the Range 1.6 MHz to 30 MHz

    Sections 3.2 and 7.2 for the final report of the technical working group


3.2 Power Line Telecommunications (PLT)

PLT is a system for voice and data transmission that makes use of power lines as
pipes for traffic within and on the way to the home. A modem, the ONELINEä Box,
allows to set up data networks from the medium-voltage power network via the low-
voltage distributed network to the customer’s in-house electrical power distribution
system.

3.2.1 PLT Access Technology

PLT Access Technology uses the local loop, i.e. a utilities' low voltage power
network, to provide public telecom services to homes and small offices. Additionally,
the ONELINEä access technology can establish point-to-point links where the
telecom signal is injected into a point in the medium or high voltage power
distribution network and received at another point.

The ONELINEä Boxes, installed in the same low voltage segment, form a network
by interacting with each other. Incoming and outgoing voice and data signals are
carried over the electric network from one customer connection to the next until they
reach a backbone connection point.

The distance from the customer’s home to the backbone connection is split up into a
number of short transmission links. This enables the transmission of data and voice
using low signal strengths according to the distance these signals must cover
enabling services to be provided to households that are far away from the backbone
connection. This allows the construction of flexible topologies tailored to suit the
existing network structure.

In order to satisfy radiated emissions regulations and to avoid the need of an
increased power to cover large distances from the transformer to the home,
ONELINE has pioneered a signal repeating mechanism that allows for “hopping”
from home to home. Because the distance between homes is generally shorter than
the distance from the transformer to any given home, this system is able to use very
low injected energy, hence meeting all current regulations for radio-frequency
radiation.




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               Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz




Figure 1: Signal Repeating Mechanism

The ONELINEä Box uses a OFDM (Orthogonal Frequency Division Multiplexing)
method and ONELINEä Technology generally is compatible with third-party
transmission technologies and systems thanks to a complement of standard
interfaces. The ONELINEä Box incorporates the following standard interfaces:
Ethernet 10BaseT, A/B, S0, E1/DSS1, RS232. Embedded asynchronous transfer
mode (ATM) and voice algorithm software gives the modem Quality of Service (QoS)
parameters necessary for real-time bi-directional service offerings such as voice
telephony.

ONELINEä Technology is SNMP (Simple Network Management Protocol) compliant,
which enables end-to-end management of the communication infrastructure
including the power lines. This allows connectivity to and high integration with
existing infrastructures, and substantially reduces costs.

The ONELINEä Box - unlike many other broadband systems - also integrates WAN
(wide area network) access technology with in-home LAN (local area network)
technology. ONELINE’s system architecture includes an in-home networking
component effectively extending the broadband access connection to multiple
devices within the home.




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                        Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz




                                               IPD




                                                     L; N; PE


                                                                                                            Fax            Telephone



                                                                                                                   RJ 45
                                                                                                                   ISDN




                                              1203545
                                                                       ONE               IPD
                                                                       LINE
                                            Meeter                     BOX    Ethernet
                                                                  RF

                                             L1 L2   L3
                                                                     HTM                    Telco      Connectivity Box
                                                          PEN
                                                                                         Termination




                                     HTM = House Terminal Module
                                     IPD = In-Home Powerline Device




Figure 2: Example for a PLC installation using ONELINE’s Technology

To achieve end-to-end connectivity, ONELINE integrates its PLC access technology
(the ONELINEä Box) with an in-home powerline device (IPD). Figure shows how
these components – together with the coupling unit (house terminal module - HTM) –
are installed in a typical household.

ONELINE’s powerline technology is embodied in the ONELINEä Box and has the
technical characteristics as shown in Table Error! Unknown switch argument.:
Frequency band                                                  1.5-30MHz
Maximum transmission level                                      0 dBm
Minimum transmission level                                      -36 dBm
Typical transmission level                                      -10 dBm
Minimum receiving level                                         -70 dBm
Transmission power                                              ca. 1 mW, dynamically regulated
Large signal resistance                                         20 dBm
Efficiency of modulation                                        5 bits per Hz
Access modem bandwidth                                          2,3 Mbps
Scalability of the voice interface                              N x 64 Kbps
Processing kernel                                               Power PC architecture
Radio interference                                              Compliant with NB 30
Modulation method                                               Modified OFDM (orthogonal frequency division multiplexing)
Error correction                                                FEC (interleaved)
Hamming distance                                                25
Management                                                      SNMP
Data encryption mode                                            Blowfish, Rijndael

Table Error! Unknown switch argument.: ONELINEä Box technical data and
characteristics


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                Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz


3.2.1.1 Frequency Plan

The operational frequency range of the ONELINEä access Technology is from 1,5 to
15 MHz. and uses a low signal transmission strength (in the milliwatt range), to keep
emissions below the tight limits required by Regulation Authorities.

By the flexible management of frequencies in the range from 2 to 30 MHz (for both
access and in-home technology), ONELINE can ensure the co-existence of PLC
access and PLC in-home systems. There is no need to preserve certain frequency
spectrums for either in-home or access applications and the whole frequency
spectrum can be used and no bandwidth is wasted. Similarly, the bandwidth
provided to customers is dynamically managed ensuring an optimum allocation of
available transmission capacity and a standard quality of service at all times.

3.2.1.2 Deployment Options

Functioning as the communications centre at the customer’s home, the ONELINEä
Box provides the technical basis for providing phone, Internet up to 2,3 Mbits, smart
home and value-added energy services over the power grid.

·   Phone Services : Local and Long Distance Services

The ONELINEä Technology can support both analogue and ISDN devices with a
capacity of up to 30 telephone channels per modem. Consumers can continue to use
their existing telephone equipment, including telephones, fax machines and
answering machines, as well as next generation ethernet and voice over internet
protocol (VoIP) based phones.

·   Internet Access at speeds of up to 2,3 Mbps

The ONELINEä Technology allows broadband internet access at speeds of up to 2,3
Mbps per household. This “always on” connection enables the customer to browse
the internet at broadband speeds and talk on the phone at the same time. The ability
to offer bundled voice and high speed internet services provides a distinct advantage
over data-only broadband solutions.

·   Smart Home Services

Smart Home Services are mainly security and convenience services. The ONELINE
ä Technology provides end-consumers with a software interface and interoperability
platform to control and automate functions in the home. The control and automation
platform acts as the “control-centre” for appliances, consumer electronic devices,
security systems, and lights within the home.

Security services provide ordinary alarm equipment with remote access. Alarm
equipment such as fire and burglary alarm devices can be coupled to the powerline
system. Convenience services provide household appliances, lights, heating and
other electric/electronic equipment with remote access.

·   Value-Added Energy Services



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                Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz


Value–Added Energy Services help utilities to increase their operational efficiency
and to save costs. These services are mainly Demand-Side Management (DSM),
Intelligent Load Shedding (ILS) and Automated Meter Reading (AMR).

DSM enables utilities to shed loads instantaneously from individual homes on their
grid. Since each home is a virtual node on the PLC access network, utilities can
target specific homes and demand full shedding or shedding on a percentage basis.
The DSM interface is web-based and leverages bi-directional messaging so utilities
can accurately monitor and control usage statistics of individual homes in real-time.

ILS allows the detection of patterns in common energy usage and uses this
information to adjust the peak load of homes automatically. AMR gathers data to
establish real time pricing systems that allow an electric utility to charge its
consumers according to their energy consumption during different times of the day.

3.2.1.3 Network Characterization

The network characterization is used to demonstrate the technical feasibility of PLT
deployment. The physical, electro-technical and electro-mechanical parameters of
the network are carefully examined in order to determine what technical adaptations
are necessary to the powerline technology to satisfy particular network, regulatory
and environmental requirements.

The network characterization includes three main analyses: an electrical and
telecommunication network topology analysis, a high frequency evaluation and a
powerline evaluation.

·   Electrical and Telecommunications Network Topology Analysis

The electrical and telecommunication network topology analysis is an evaluation of
typical network topologies, typical installations and operating scenarios, as well as
customer access installations and the materials used. Customer and backbone
access requirements for telecommunications are also considered.

Some of the points to evaluate in a network topology include:

-   the relationship between high voltage (HV) and medium voltage (MV)
    infrastructure compared to the low voltage (LV) distribution (distances from
    HV/MV to LV sites, connection of LV transformers to the HV/MV grid, distances
    between LV sites, size, number and cable types of the communication lines “pilot
    wires”, use of optical fibre deep into the network, etc.),

-   the transformer size (typical residential LV transformer sizes of 100 KVA, 200
    KVA, 400 KVA, 630 KVA and 1 MVA, LV transformer size in non-residential
    areas),

-   the transformer housing used for the LV transformers and associated equipment
    (brick or concrete building protected from the environment with heating / air
    conditioning, how is the equipment pad mounted (base plate), space available for
    telecommunications equipment, equipment expected to be installed in its own
    outdoor cabinet, min/max temperature, humidity shock and vibration, etc.),


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                 Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz


-   the transformer bus bars and fuses (positions, where it is permitted to make
    connections to the bus bars for communications purposes, use of back feeding to
    increase the service availability in case of a LV power break down in parts of the
    residential area, metal enclosures or covers used in the area of the bus bars or
    fuses, etc.)

-   the low voltage distribution cable/line type (cable and overhead lines, cable types,
    etc.)

-   the distribution cable practice (outer casing used as a neutral, existence of a
    copper foil wrap around the neutral, etc.)

-   the distribution network distances (distance from LV transformer to homes),
    distribution to the service cable (number of houses per connection point, number
    of homes per mini-pillar, connection of street lights, drop into the home with a
    coaxial neutral, wires twisted, etc)

-   the distribution network voltages and its standards.

·   High Frequency Evaluation

The high frequency evaluation is carried out in low voltage segments. Basic physical
parameters of the network are evaluated to identify appropriate network parameters
and the prediction of the behavior of the networks. Typical powerline-relevant
parameters are attenuation, based on the network and frequency involved, time and
network dependency of noise and impedance, and the impedance and frequency
dependent radiation characteristics of the network.

·   Powerline Evaluation

The aim of the powerline evaluation is to obtain relevant data concerning achievable
data quality and performance. It consist of three phases:

First, an evaluation system is installed. The evaluation system consists of a point-to-
point connection in the low voltage segment without actual customer and backbone
access. It uses internal measurement procedures in order to carry out long-term bit
error rate (BER) tests, error analysis and performance observations.

Second, a powerline trial is carried out. This trial consist on a connection of x (x= less
than five) households. The purpose of the trial is to test the quality and performance
of services delivered via powerline technology over a period of time. The trial tests
also demonstrate the basic technical feasibility of the powerline system and
interoperability of its interfaces. Access to the traditional telecommunication service
provider is not interrupted during the trial.

Third, a powerline pilot system is installed connecting 20 households. This
demonstrates the system interoperability, manageability and performance in a larger
and near fully operational context. Access to the traditional telecommunication
service provider is not interrumpted during the pilot.

3.2.1.4 EMC Mitigation


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                 Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz


The ONELINEä Access Technology has passed the EMC Mitigation Tests in
Germany. The purpose of the EMC Mitigation Test was to prove the ability of the
ONELINEä Box to work satisfactorily in its intended surroundings without
interference to its function from external sources or interference to adjacent
equipment, appliances or persons.

The functionality of the ONELINEä Box was tested in different scenarios with the
aim, first, to evaluate the electrical integrity, i.e., if the ONELINEä Box is unaffected
by the normal environment conditions that usually appear in the intended
surroundings and secondly, whether the ONELINEä Box emits undesirable signals,
i.e., whether the ONELINEä Box disturbs other appliances in the surrounding area.

The systematic EMC Mitigation tests carried out with the ONELINE access
technology were:

First, an evaluation of the system integrity against fast transient electric signals
(Burst-Test). The Burst-Test was executed according to DIN EN 6100-4-4 without
grounding of the casing in the following situations:

-   Spike frequency power supply 5 kHz

-   1000 V energy supply / PE

-   500 V data management / interfaces

-   Burstlenght of 15 m

-   Period 300 ms

The tests on the power supply between L, N were successfully executed with positive
and negative polarity of the impulses.

Secondly, an evaluation of the system inegrity against high-tension impulses. The
examination of the system integrity through management-tied impulse-disturbances
was executed according to EN DIN 6100-4-5. The impulse-disturbances were directly
connected into the corresponding conductor L + N with the following qualities:

-   Umax = 1000V

-   Rise time = 1,2 µs

-   Half period = 50 µs

-   5 Impulses with positive and negative polarity

-   1 Impulse per second

3.2.2 PLT Home Networks

PLT Home Networks (ONELINEä InHome Technology) uses in-building power
cabling to set up private local area networks. The telecom signal is transmitted on
the domestic power cable via the residential gateway. PLT Home Networks can be
used as either a broadband data transmission medium to connect a PC and its
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                Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz


peripherials or as a narrow band data transmission medium to monitor and control
electrical appliances i.e. lights, heating systems, household appliances, and stereos.

Once the customer’s house is fitted with the ONELINEä Box, a broadband internet
connection exists. To extend the connection to the PC in the living space, an in-
home powerline device (IPD) is required.

The IPD allows the transmission of voice and data signals through existing power-
lines within the home to and from any power socket. The IPD is a power-line-to-
ethernet transceiver embedded in a wall module. This wall module plugs into any
electrical socket and offers the customer an ethernet jack and phone jacks to
connect PCs. The main purpose of the IPD is to extend the ethernet and phone
interfaces on the ONELINEä Box to any socket where the customer wishes to send
and receive data and/or voice.

For ONELINEä InHome Technology’s support to Smart Home Services (the
automation and control of electrical appliances), a CEbus is used as the core
technology. CEbus provides a standardized and proven technology for narrowband
control and automation applications. Many manufacturers of white-goods appliances
and consumer electronics devices are specifying CEbus into designs of their devices.
CEbus is a well-respected emerging standard for devices that will be automated in
the future.

For narrowband control and automation applications, smart-house software has to be
pre-installed in the IPD. The software allows for control and automation of electrical
appliances. By connecting household appliances to the software, they become
sufficiently “intelligent” to receive automation commands and operate according to
pre-determined or controllable rules.

Because PLT’s is available throughout a home, it serves as a perfect medium for
attaching wireless transceivers. The power-line inside the home serves as the
“backbone network” and wireless modules can be plugged into the power socket to
provide each room with wireless connectivity without regard for walls and structures
that might normally impede the wireless signal. ONELINEä InHome Technology
coupled with wireless provides a total networking solution where “plugged in” devices
are served by the powerline connection, and the powerline connects multiple
wireless modules in different rooms to the broadband access connection (modem)
providing total connectivity throughout the entire home.




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                Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz




Figure Error! Unknown switch argument.: Integration of PLC and wireless
technologies

3.2.2.2 EMC Mitigation

The ONELINEä InHome Technology has passed the same EMC Mitigation tests as
the ONELINEä Access Technology. First, the system integrity was evaluated against
fast transient electric signals (Burst-Test) and second against high-tension impulses.

7.2 PLT Field Measurements

The PLT field measurements conducted by ONELINE AG included an Access Data
Transfer Rate, and an Access Radiated Emissions Test for the ONELINEä Access
Technology and, for the ONELINEä InHome Technology, an In-Home Data Transfer
Rate, an In-Home Radiated Emissions Test, a Test of the Privacy Between Homes, a
Dynamic Range and a VDE Mark Test.

Field measurements were made in small offices and at homes in the German region
of Sachsen-Anhalt, at maximum transmit power, i.e. data rates of 1-4 Mbps between
sockets.

The measurements in small offices were conducted in offices of 12m x 42m, on
average, and in different floors of three story structures.

The measurements in homes were conducted in 4-level households (basement, two
floors, and a loft), where the power meter was located in the basement. There are,
on average, three meters in the basement; a main meter and two secondary meters.
The secondary meters allow the houses to be split into two apartments. The breaker
panels associated with each secondary meter are located on the first and second
floors. The size of the basements on each floor (excluding lofts) were on average
10m x 12m.

7.2.1 PLT Access Technology

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                Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz


·   Access Data Transfer Rate

Access data transfer rates between a power substation and a house were measured.
Two 20 ohm source impedance units were modified to transmit and receive signals
through the SMA test connector. These units were connected to the low voltage
power lines at the substation and house through the ONELINE™ coupling circuits.
The units were configured to transmit maximum power.

·   Access Radiated Emissions Test

Field strength measurements were taken three metres from the exterior wall nearest
the injection point for the signal at both the power substation and houses.

7.2.2 PLT Home Networks

·   In-Home Data Transfer Rate Measurements

In-Home Data Transfer Rate Measurements were conducted in small offices and in
households.

In-Home data transfer rate measurements in small offices were collected for three
configurations of the units. First, a 20 ohm source impedance, second, a 100 ohm
source impedance and finally, a 20 ohm source impedance with transmitted power
reduced 15 dB.

At homes, data transfer rate measurements were collected for three configurations of
the units. First, 20 ohm source impedance. Second, a 100 ohm source impedance
and finally, a 20 ohm source impedance with transmitted power reduced 11 dB. In
addition to varying the configuration of the units, two positions for the receiving unit
were used in the houses. One position was located next to the power meter in the
basements. The second position was located on the first floors.

·   In-Home Radiated Emissions Test

In-Home Radiated Emissions Tests were carried out in households. The prescan
spectrum was captured with and without the units transmitting. The prescan
spectrum was used to select frequencies for measurement. The measurements
frequencies were selected from the 16 carrier centre frequencies of the units. The
NB30 field strength limits identified in the following sections were calculated with the
following equation:

         Limit = 40 – 8.8*log10 (frequency); where frequency units are MHz

·   Test of the Privacy Between Homes

Privacy Tests were conducted between two houses. A single house always
separated the test houses. The units were configured for maximum transmit power.

·   Dynamic Range Test

The receiver dynamic range was demonstrated. For the demonstrations, two 20 ohm
source impedance units were modified to transmit and receive signals through the
SMA test conductor. Normally, these units were configured to transmit and receive
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               Compatibility of VDSL & PLT With Radio Services in the Range 1.6 MHz to 30 MHz


signals through the AC power entry module. The units were cabled together with
various attenuator values.

·   VDE Mark Test

VDE Mark Tests were conducted. The VDE Mark indicates conformity with the VDE
standards of European or internationally harmonized standards and confirms
compliance with protective requirements of the applicable EC Directive(s).

The VDE Marks Licence Certificate confirms compliance with standards and the
requirements of the Appliance Safety Law (GSG). It also forms the basis for the EC
Declaration of Conformity and CE marking by the manufacturer or his authorized
representative. Finally, the VDE Marks Licence Certificte confirms compliance with
the standards of the EC Low-voltage Directive 73/23/EEC and its Amendments.

Testing was based on the Harmonization Documents (HD) listed in the HAR
Agreement. Products (harmonized power cables) tested and found in compliance
with the requirements of the mentioned standards may be marked with the VDE
HARmonization Marking.




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